Research will be conducted in the following areas: A. Data is being obtained on the distribution of metabolites and the end products of differentiation in each of the two major cell types. Separate kinetic models will then be constructed for each type. B. A program used in the analysis of radioactive tracer studies will be modified to handle the specific radioactivity of atoms within molecules. C. Trehalose-6-phosphate synthetase exists in a latent form, and can be unmasked. The active enzyme will be extensively purified and characterized.